Prognostic value of olfactory evoked potentials in patients with post-infectious olfactory dysfunction

Area of Science:

• Neuroscience
• Otolaryngology
• Clinical Medicine

Background:

• Post-infectious olfactory dysfunction (PIOD) presents a challenge for accurate prognostic assessment.
• Existing prognostic factors for PIOD primarily focus on demographic data.
• Novel predictors are needed to guide clinical management and patient expectations.

Purpose of the Study:

• To investigate the utility of event-related potentials (ERPs) as a predictive tool for olfactory recovery in PIOD patients.
• To identify specific ERP parameters associated with olfactory improvement.

Main Methods:

• Retrospective analysis of 61 PIOD patients.
• Olfactory function assessed using the Sniffin' Sticks test at baseline and after one year.
• Responder group defined by a Threshold-Discrimination-Identification (TDI) score increase of ≥6 points.
• Event-related potentials (ERPs), including olfactory (oERPs) and trigeminal (tERPs), recorded before treatment.

Main Results:

• The presence of olfactory ERPs (oERPs) was significantly higher in the responder group compared to non-responders (P=0.007).
• Trigeminal ERPs (tERPs) did not show a significant difference between groups (P=0.346).
• Logistic regression identified duration of olfactory dysfunction, initial olfactory threshold, and N1 latency in oERPs as significant predictors of olfactory improvement.

Conclusions:

• Duration of olfactory dysfunction, initial olfactory threshold, and N1 latency in oERPs are associated with olfactory improvement in PIOD.
• oERPs show potential as a biomarker for predicting olfactory recovery in PIOD.
• These findings can assist clinicians in providing prognoses for PIOD patients.